#+SETUPFILE: "doc/basho-doc-style.iorg"
Welcome to Riak.
* Overview
Riak is a distributed, decentralized data storage system.
Below, you will find the "quick start" directions for setting up and
using Riak. For more information, browse the following files:
* README: this file
* TODO: a list of improvements planned for Riak
* LICENSE: the license under which Riak is released
* apps/ the source tree for Riak and all its dependencies
* doc/
- basic-setup.txt: slightly more detail on setting up Riak
- basic-client.txt: slightly more detail on using Riak
- architecture.txt: details about the underlying design of Riak
- index.html: the root of the edoc output of 'make docs'
* Quick Start
This section assumes that you have copy of the Riak source tree. To get
started, you need to:
1. Build Riak
2. Start the Riak server
3. Connect a client and store/fetch data
** Building Riak
Assuming you have a working Erlang (R13B03 or later) installation,
building Riak should be as simple as:
#+BEGIN_EXAMPLE
$ cd $RIAK
$ make all rel
#+END_EXAMPLE
** Starting Riak
Once you have successfully built Riak, you can start the server with the
following commands:
#+BEGIN_EXAMPLE
$ cd $RIAK/rel/riak
$ bin/riak start
#+END_EXAMPLE
Now, verify that the server started up cleanly and is working:
: $ bin/riak-admin test
Note that the $RIAK/rel/riak directory is a complete, self-contained instance
of Riak and Erlang. It is strongly suggested that you move this directory
outside the source tree if you plan to run a production instance.
** Connecting a client to Riak
Now that you have a functional server, let's try storing some data in
it. First, start up a erlang node using our embedded version of erlang:
#+BEGIN_EXAMPLE
$ erts-<vsn>/bin/erl -name riaktest -setcookie riak
Eshell V5.7.4 (abort with ^G)
(riaktest@example.com)1>
#+END_EXAMPLE
Now construct the node name of Riak server and make sure we can talk to it:
#+BEGIN_EXAMPLE
(riaktest@example.com)4> RiakNode = riak_util:str_to_node(riak).
(riaktest@example.com)2> net_adm:ping(RiakNode).
pong
(riaktest@example.com)2>
#+END_EXAMPLE
We are now ready to start the Riak client:
#+BEGIN_EXAMPLE
(riaktest@example.com)2> {ok, C} = riak:client_connect(RiakNode).
{ok,{riak_client,'riak@example.com',<<4,136,81,151>>}}
#+END_EXAMPLE
Let's create a shopping list for bread at /groceries/mine:
#+BEGIN_EXAMPLE
(riaktest@example.com)6> O0 = riak_object:new(<<"groceries">>, <<"mine">>, ["bread"]).
O0 = riak_object:new(<<"groceries">>, <<"mine">>, ["bread"]).
{r_object,<<"groceries">>,<<"mine">>,
[{r_content,{dict,0,16,16,8,80,48,
{[],[],[],[],[],[],[],[],[],[],[],[],[],[],...},
{{[],[],[],[],[],[],[],[],[],[],[],[],...}}},
["bread"]}],
[],
{dict,1,16,16,8,80,48,
{[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],...},
{{[],[],[],[],[],[],[],[],[],[],[],[],[],...}}},
undefined}
(riaktest@example.com)3> C:put(O0, 1).
#+END_EXAMPLE
Now, read the list back from the Riak server and extract the value
#+BEGIN_EXAMPLE
(riaktest@example.com)4> {ok, O1} = C:get(<<"groceries">>, <<"mine">>, 1).
{ok,{r_object,<<"groceries">>,<<"mine">>,
[{r_content,{dict,2,16,16,8,80,48,
{[],[],[],[],[],[],[],[],[],[],[],[],...},
{{[],[],[],[],[],[],
[["X-Riak-Last-Modified",87|...]],
[],[],[],...}}},
["bread"]}],
[{"20090722191020-riaktest@example.com-riakdemo@example.com-266664",
{1,63415509105}}],
{dict,0,16,16,8,80,48,
{[],[],[],[],[],[],[],[],[],[],[],[],[],...},
{{[],[],[],[],[],[],[],[],[],[],[],...}}},
undefined}}
(riaktest@example.com)5> %% extract the value
(riaktest@example.com)5> V = riak_object:get_value(O1).
["bread"]
#+END_EXAMPLE
Add milk to our list of groceries and write the new value to Riak:
#+BEGIN_EXAMPLE
(riaktest@example.com)6> %% add milk to the list
(riaktest@example.com)6> O2 = riak_object:update_value(O1, ["milk" | V]).
{r_object,<<"groceries">>,<<"mine">>,
[{r_content,{dict,2,16,16,8,80,48,
{[],[],[],[],[],[],[],[],[],[],[],[],[],[],...},
{{[],[],[],[],[],[],
[["X-Riak-Last-Modified",87,101,100|...]],
[],[],[],[],[],...}}},
["bread"]}],
[{"20090722191020-riaktest@example.com-riakdemo@example.com-266664",
{1,63415509105}}],
{dict,0,16,16,8,80,48,
{[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],...},
{{[],[],[],[],[],[],[],[],[],[],[],[],[],...}}},
["milk","bread"]}
(riaktest@example.com)7> %% store the new list
(riaktest@example.com)7> C:put(O2, 1).
ok
#+END_EXAMPLE
Finally, see what other keys are available in groceries bucket:
#+BEGIN_EXAMPLE
(riaktest@example.com)8> C:list_keys(<<"groceries">>).
{ok,[<<"mine">>]}
#+END_EXAMPLE
* Server Management
** Configuration
Configuration for the Riak server is stored in $RIAK/rel/riak/etc
directory. There are two files:
- vm.args
This file contains the arguments that are passed to the Erlang VM
in which Riak runs. The default settings in this file shouldn't need to be
changed for most environments.
- app.config
This file contains the configuration for the Erlang applications
that run on the Riak server.
More information about this files is available in doc/basic-setup.txt.
** Server Control
*** bin/riak
This script is the primary interface for starting and stopping the Riak
server.
To start a daemonized (background) instance of Riak:
: $ bin/riak start
Once a server is running in the background you can attach to the Erlang
console via:
: $ bin/riak attach
Alternatively, if you want to run a foreground instance of Riak, start it
with:
: $ bin/riak console
Stopping a foreground or background instance of Riak can be done from a
shell prompt via:
: $ bin/riak stop
Or if you are attached/on the Erlang console:
: (riak@example.com)1> q().
You can determine if the server is running by:
: $ bin/riak ping
*** bin/riak-admin
This script provides access to general administration of the Riak server.
To join a new Riak node to an existing cluster:
#+BEGIN_EXAMPLE
$ bin/riak start # If a local server is not already running
$ bin/riak-admin join <node in cluster>
#+END_EXAMPLE
(Note that you must have a local node already running for this to work)
To verify that the local Riak node is able to read/write data:
: $ bin/riak-admin test